One couple scored big when they came across a smelly find that could bring in more than $70,000.

Gary and Angela Williams were walking on a beach in the United Kingdom when they smelled a foul odor, the Mirror reports. The stench was coming from a "rock" about the size of a rugby ball, which turned out to be ambergris, sometimes known as whale vomit.

Ambergris is used to extend the scent of perfume and is very valuable. The substance takes years to form and can float around in the ocean for a long time before coming ashore.

“It was down a section of the beach where no one really walks. It smells too bad though. It's a very distinctive smell, like a cross between squid and farmyard manure,” he told the Mirror. “It feels like a rock-hard rubber ball. Its texture is like wax, like a candle. When you touch it you get wax sticking to your fingers."

According to The Guardian, the couple, who are from Lancashire, are talking with potential buyers from France and New Zealand about selling the 3.5-pound chunk for around $70,000. The Guardian adds that a similar, but smaller piece was found on a beach in Wales and sold for over $15,000.

The couple are hoping to sell the piece so they can use the money to buy a mobile home.

"If it is worth a lot of money, it will go a long way toward buying us a static caravan. It would be a dream come true,” Gary told Mirror, referring to the British term for a mobile home.

Read more at Mirror and The Guardian.